What Is Multiple Myeloma? A Look Inside This Bone Marrow Cancer

Here’s how this cancer of plasma cells develops.

When you think of a blood cancer, you may automatically think it’s a type of cancer that affects that red stuff coursing through your veins. While that’s not completely incorrect, blood is far more complex than what meets the eye. There are actually many different types of blood cancer that affect different microscopic parts of the blood.

One of these blood cancers is called multiple myeloma. Multiple myeloma is a cancer of the plasma cell, which is a type of white blood cell. These cells live in the bone marrow and are key for healthy immune system function. Normally, those white blood cells make antibodies to help fight off infection.

This abnormal antibody, called M protein, floats around and can be toxic to kidneys or attack other parts of the body. In fact, the hallmark characteristic of multiple myeloma is a high level of M protein in the blood.

“So instead of helping you fight an infection, the [abnormal plasma cells] just sort of accumulate,” says Dr. Rossi. These “misbehaving” cells then crowd out the normal, infection-fighting plasma cells, which can lead to low blood counts and low immune cells, increasing the risk of infections and other multiple myeloma complications.

What’s more, because the tumor cells are in the bone marrow, they can affect regular bone marrow function and cause damage to the bones.

Diagnosing Multiple Myeloma

Catching multiple myeloma early can be difficult. By the time most people experience multiple myeloma symptoms, such as fatigue or bone pain, the disease has likely progressed to an advanced stage.

Multiple myeloma is often caught during a routine blood test. “[Myeloma] starts off with the presence of the abnormal antibody and leads to a referral to a hematologist for a complete testing,” says Dr. Rossi.

If a doctor suspects multiple myeloma, they may conduct imaging tests (such as an MRI or CT scan), a urine sample to assess a patient’s kidney function and the presence of the M protein, or a bone marrow biopsy to get a sample of the tissue.

If a multiple myeloma diagnosis is confirmed, your doctor will discuss your treatment options. “It's a great time to be treating myeloma because we've had so many advances in recent years,” says Dr. Rossi. “So, even though myeloma is considered incurable, right now we try to get you into remission and then make it last as long as possible, which for many patients is years.”